title: Optimization of efficiency-loss figure of merit in carrier-depletion silicon Mach-Zehnder optical modulator.
abstract: In this paper we study the optimization of interleaved Mach-Zehnder silicon carrier depletion electro-optic modulator. Following the simulation results we demonstrate a phase shifter with the lowest figure of merit (modulation efficiency multiplied by the loss per unit length) 6.7 V-dB. This result was achieved by reducing the junction width to 200 nm along the phase-shifter and optimizing the doping levels of the PN junction for operation in nearly fully depleted mode. The demonstrated low FOM is the result of both low V(π)L of ~0.78 Vcm (at reverse bias of 1V), and low free carrier loss (~6.6 dB/cm for zero bias). Our simulation results indicate that additional improvement in performance may be achieved by further reducing the junction width followed by increasing the doping levels.
authors.forename: Ilya
authors.initials: I
authors.lastname: Goykhman
authors.forename: Boris
authors.initials: B
authors.lastname: Desiatov
authors.forename: Shalva
authors.initials: S
authors.lastname: Ben-Ezra
authors.forename: Joseph
authors.initials: J
authors.lastname: Shappir
authors.forename: Uriel
authors.initials: U
authors.lastname: Levy